This proposed work focuses on: a) the hormonal regulation of sex accessory organ epithelium and muscle function; b) possible abnormalities in the sex hormone environment of the epithelium and muscle of hyperplastic prostate glands; and c) the potential therapeutic value of the combined use of an anti-androgen and an anti-estrogen in the treatment of prostatic neoplasia. These studies will concentrate on the separated epithelium and muscle of the guinea pig seminal vesicle and on the separated epithelium and muscle of normal and hyperplastic canine prostate glands. In the studies of the hormonal regulation of epithelium and muscle function, the experiments are designed to test the hypothesis that both of these tissue types may be androgen sensitive and that the estrogens may also be significant contributors to sex accessory organ growth, particularly the growth of the muscle of the organ. Furthermore it is to be considered that abnormalities in androgen and estrogen dynamics in the epithelium and stroma may be significant factors in the neoplastic growth of the prostate gland. Extensive use of anti-androgens and anti-estrogens will be made not only to investigate the intracellular significance of the androgens and estrogens in epithelium and fibromuscular stroma but to develop improved selective antagonism of neoplastic prostate growth by combined inhibition of epithelium and stroma function. The primary parameters to be measured include DNA, RNA, protein, distribution binding and metabolism of 3H-hormones and radioimmunoassay of selected androgens and estrogens.